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31.
In this work, flow cytometry was utilized to analyze the initial vegetative growth of the model fungus Aspergillus nidulans as measured by the number of events increasing size and internal complexity. It was established the ideal parameters for the analysis of conidial populations, whose growth was followed after germination in glucose or sucrose. While glucose in culture increased growth several magnitudes in comparison to control cultures in saline, growth was less intense in cultures amended with sucrose. Results indicated that flow cytometry could be a useful tool to study fungal germination and initial growth since it allowed rapid identification of different populations by means of their increasing in size and granularity with good reproducibility and without the need for direct observation and count of individual cells.  相似文献   
32.
Background:  Poor asthma control is associated to high morbidity. The objective of this study was to assess the association between adherence rates to beclomethasone dipropionate (BDP) and the degree of asthma control.
Methods:  A cohort concurrent study was carried out for 12 months with 122 asthmatic patients, aged 3–12 years, randomly selected in a pediatric pulmonology outpatient clinic, who received BDP free of charge. Adherence rates were verified by pharmacy records. Clinical control was assessed through a scoring system comprised four variables (nocturnal and morning symptoms, limitation of physical activities and exacerbations). Total score was 16 points. Patients whose score was below or equal to two were considered controlled (group 1), and patients whose score was above or equal to three were considered uncontrolled (group 2). For patients able to perform spirometry, we considered as controlled the patients with forced expiratory volume in 1 s (FEV1) equal to or above 80% of the predicted value, and as uncontrolled the patients with FEV1 below 80%.
Results:  Fewer than half (40.3% maximum) of the 122 patients maintained asthma control. Median adherence rate of groups 1 and 2 were 85.5% and 33.8%, ( P  < 0.001) in the 4th month, 90.0% and 48.0% ( P  < 0.001) in the 8th month and 84.4% and 47.0% in the 12th month ( P  < 0.001), respectively.
Conclusion:  In all periods, there were statistically significant differences in adherence rates for maintaining or not maintaining the asthma control. Optimal asthma control entailed adherence rate higher than 80%. Strategies for reducing asthma morbidity should include a regular monitoring of adherence to inhaled steroids.  相似文献   
33.
Congenital insensitivity to pain with anhidrosis (CIPA) or hereditary sensory and autonomic neuropathy type IV is a rare, autosomal recessive neurologic disorder, characterized by absence of reaction to painful stimuli, mental retardation, self- mutilating behavior, anhidrosis, and recurrent episodes of hyperthermia. Mutations in the neurotrophic tyrosine kinase receptor 1, a receptor phosphorylated by nerve growth factor, have been documented in diverse ethnic groups. We identified the same novel nonsense mutation in two unrelated families of Moroccan Jewish descent, each with two affected siblings. This possible founder mutation may trace to the rural Jewish village in southern Morocco from where both these families originated. Genetic screening for the causative mutation among 300 unrelated Moroccan Jews did not reveal carriers for the causative mutation, thus excluding high risk for CIPA in this ethnic subpopulation.  相似文献   
34.
Structuring a safer donor-replacement program   总被引:1,自引:0,他引:1  
BACKGROUND: Replacement donors are more likely than volunteer donors to have positive or abnormal tests for transfusion-transmissible disease. In an effort to increase the donor pool, workers sought to identify a safer replacement-donor subgroup that may be acceptable for routine donations. STUDY DESIGN AND METHODS: In a retrospective review and cohort study, the replacement-donor effect was separated from the new- donor effect. The relative effect the replacement donor has on the risk of transfusion-transmissible diseases, donor retention, and frequency of returning donations was then quantified by comparison against the effect of repeat volunteer donors. RESULTS: The replacement donor had 3.1 times the risk and 0.72 times the donor retention rate and made 0.81 times as many returning donations as the repeat volunteer donor. The figures for the new-donor effect were similar. The two risks were additive, making a new replacement donor particularly hazardous. If replacement donations only from repeat replacement donors were considered, the donor risk and the number of donations per returning donor were made comparable to those for the general (combined) volunteer donor. CONCLUSION: The negative effect of the replacement donor is similar in magnitude to that of the new volunteer donor. A replacement-donation program targeting repeat replacement donors has an acceptable risk profile and may be a valuable adjunct to the collection of blood from general volunteer donors.  相似文献   
35.
36.

Background

Aging is a multifactorial process that leads to changes in the quantity and quality of skeletal muscle and contributes to decreased levels of muscle strength.

Objective

This study sought to investigate whether the isometric muscle strength, fat-free mass (FFM) and power of the electromyographic (EMG) signal of the upper and lower limbs of women are similarly affected by aging.

Method

The sample consisted of 63 women, who were subdivided into three groups (young (YO) n=33, 24.7±3.5 years; middle age (MA) n=15, 58.6±4.2 years; and older adults (OA). n=15, 72.0±4.2 years). Isometric strength was recorded simultaneously with the capture of the electrical activity of the flexor muscles of the fingers and the vastus lateralis during handgrip and knee extension tests, respectively. FFM was assessed using dual-energy X-ray absorptiometry.

Results

The handgrip strength measurements were similar among groups (p=0.523), whereas the FFM of the upper limbs was lower in group OA compared to group YO (p=0.108). The RMSn values of the hand flexors were similar among groups (p=0.754). However, the strength of the knee extensors, the FFM of the lower limbs and the RMSn values of the vastus lateralis were lower in groups MA (p=0.014, p=0.006 and p=0.013, respectively) and OA (p=0.000, p=0.000 and p<0.000, respectively) compared to group YO.

Conclusions

The results of this study demonstrate that changes in isometric muscle strength in MLG and electromyographic activity of the lower limbs are more pronounced with the aging process of the upper limb.  相似文献   
37.
38.
Azidothymidine (AZT) and interferon alpha (IFN-alpha) are among the drugs showing strong in vitro activity against the human immunodeficiency virus type-1 (HIV-1). Each drug, however, has significant toxicity against normal marrow progenitor cells that frequently proves dose-limiting in patients. In this study, AZT and recombinant IFN-alpha 2a (rIFN-alpha 2a) were tested as single agents and in combination against normal myeloid (CFU-GM) and erythroid (BFU- E) colony forming cells in a standard methylcellulose culture assay. The data were analyzed using a quantitative computerized analysis based on the median-effect principle and the isobologram equation as described by Chou and Talalay (Adv Enz Regul 22:27, 1984). The ED90 for BFU-E and CFU-GM inhibition was then compared with previously measured in vivo plasma levels of each drug and the ED90 for the anti-HIV-1 effect in vitro. We demonstrate that (a) the drugs are strongly synergistic in inhibiting marrow progenitor cell growth and that this synergism occurs at drug levels that are within the range of measured plasma levels in phase I clinical trials, (b) BFU-E are more sensitive than CFU-GM to the inhibiting effects of AZT, rIFN-alpha 2a or both drugs in combination, (c) the drug concentrations in combination that synergistically inhibit bone marrow progenitors are much higher than those required to inhibit HIV-1 replication in vitro, and (d) the anti- HIV-1 effect for the combination of AZT and rIFN-alpha 2a was clearly superior to the effect of AZT or rIFN-alpha 2a alone as indicated by the combination index and the dose-reduction index. These data suggest that substantially lower doses of AZT and rIFN-alpha than those currently being tested in clinical trials might not only maintain a strong synergistic anti-HIV-1 effect but might also avoid significant hematologic toxicity.  相似文献   
39.
McGowan  EB; Detwiler  TC 《Blood》1985,65(4):1033-1035
The effect of a zinc metalloprotease from Serratia marcescens on platelet surface glycoproteins (GP) Ib and V was analyzed. Increasing protease treatments caused progressive loss of GP Ib with appearance of the major fragment, glycocalicin, in the supernatant solution. No GP V was detected in the supernatant solution, and protease-pretreated platelets had the same capacity as control platelets to release fragment 1 of GP V in response to thrombin. The Serratia protease- pretreated platelets did show the lag before thrombin-induced dense granule secretion, characteristic of platelets modified by pretreatment with other nonstimulating proteases. Treatment with Serratia protease gives the only demonstrated selective loss of GP Ib without apparent effect on GP V. It suggests that GP V (1) does not depend on GP Ib for its association with platelets and (2) is not the substrate for protease modification of platelet function.  相似文献   
40.
Novotny  WF; Palmier  M; Wun  TC; Broze  GJ Jr; Miletich  JP 《Blood》1991,78(2):394-400
The lipoprotein-associated coagulation inhibitor (LACI) is present in vivo in at least three different pools: sequestered in platelets, associated with plasma lipoproteins, and released into plasma by intravenous heparin, possibly from vascular endothelium. In this study we have purified the heparin-relesable form of LACI from post-heparin plasma and show that it is structurally different from lipoprotein LACI. The purification scheme uses heparin-agarose chromatography, immunoaffinity chromatography, and size-exclusion chromatography and results in a 185,000-fold purification with a 33% yield. Heparin- releasable LACI (HRL), as analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis, under reducing conditions, appears as a major band at 40 Kd and a minor band at 36 Kd. Immunoblot analysis suggests that the 36-Kd band arises from carboxyl-terminus proteolysis that occurs during the purification. HRL has a specific activity similar to that of HepG2 or lipoprotein LACI. HRL and lipoprotein LACI combine with lipoproteins in vitro while purified HepG2 LACI does not. I125-labeled HRL, injected into a rabbit, is cleared more slowly than I125-labeled HepG2 LACI, which may be due to attachment to lipoproteins in vivo. Preliminary evidence suggests that HRL is associated with vascular endothelium, possibly by attachment to glycosaminoglycans.  相似文献   
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